•M3 5 8701 五、新型說明： 【新型所屬之技術領域】 本創作係有關於-種防急速損壞之起子頭結構，詳而言之係關於一種 可於使用時延長發生變形之時間以供警示使用社確保作業安全之設計。 【先前技術】 按，台灣為工業技術王國，從製造、加工到維修，無—不是技術先進、 製造難，因此工霞品深受世界各國錢，從汽車製造職子加工，都 為本國帶來豐饒的收益，而產業在進行諸多作業時最常使用的設備即為手 工具’軸部份具高度技術與危險環境之作f已漸由機器所取代，作是基 本之加工與維修須賴以手工具之輔助才能完成，因此各國業者無一不在研 發更麯、更人性化以及製造成本更為低廉之衫具結構。 在眾夕手工具中’起子頭型態之手工具為使用及製造最為頻繁者，尤 其為了能讓使用者於作業時方便替換不同起子頭型態之工具，相關製造業 者更研發了可她㈣打H設彳彡財__之奸頭，俾使用 者得視情況_輕者髓至工碰柄之起子桿上骑行作業， 此先關業界巾乡有馳侧之設計及料。 〃 習用之起子頭請參閱第-圖圖式所示，其係包括一驅動段以及—杜人 段92，該驅動段91與結合段92之長度相當，而驅動段91之直徑僅略小於 、^又92 ’且結合段92係用以與起子桿或氣動工具結合，藉此其可受轉動 使驅動段91旋轉鎖固件進入欲結合對象内固定，然而為求驅動段91可與 鎖口件滅結合，其—端會設計形成可與鎖固件嵌合之型態，即如第—圖 起子碩之IE動I又91所顯示將端部部份向内削除而成十字態樣，而由於起子 •M358701 頭此種杯狀之結構说力時’起子桿所承受之轉剪應力「咖丨咖1加ar St謂」係為扭力值乘上斷面半徑再除崎面之極慣性矩「她『醜⑽ -lnertia」’而驅動段91與結合段92係銜接成型，故其屬串聯桿件之型態， ._動段91與結合段92所受之扭力_，因而根據上述扭轉剪應力之計 异式下’扭力值相同，斷面半徑越小，則極慣性矩越大，造成扭轉剪應力 、加’因此狀起侧其十字端部之斷醉徑為整體最小之處，因 而其亦為魅_剪應力最大讀，此《起侧最容祕雜力破壞之 籲S ’即如第九圖圖式所示（為求令人明瞭易懂，該習用起子頭之扭力實驗 曲線圖係擺置於第九圖以方便與本創作分析比較，合先敘明），該曲線圖之 縱軸為扭力變形（即扭财應力造成之轉賴形），而横姉為起子頭所受 之扭力值，當扭力值提料，起子_產生扭力變形，而當到達起子頭受 扭力而能彈性復原之最大值，即所謂扭力之降伏點「yieid p〇此時，曲 線之走向物止於降伽處，其代表起子麟於降伏點處發生破壞，且所 顯示者係為十字端部發生斷裂（如第二圖圖式所示），而觀察曲線圖後可發 鲁現，其是在扭力值到達降伏點時馬上發生破壞，在降伏點後並無緩衝之扭 力變形曲線走向（即降伏點後之塑性變形區域「_仙_」，塑性變性 區域前為彈性變形區域「elastlc咖」，物體於彈性變形區域中之變形可 於文力卸載後彈性回復至原狀，而塑性變形區域會產生永久變形，即便受 力卸載仍不能恢復至原狀），故使用者在使用該種起子頭時，即容易突然端 .部發生斷裂，造成斷裂端部彈出傷人，或使用者因慣性作用往前傾撞之危 險; ”（子頭如第二圖圖式所示，該驅動段犯之長度較結合段94 4 'M358701 :94為小’故其可視為兩段不同長度、直徑之桿件串 聯銜接之鶴，當該_之起子頭受顺力時，由於根據前述承受扭力相 :，.彳轉剪應力係與極慣性矩成反比，因而驅動段93所受之扭轉 J應力U又94為大，故驅動段⑽會較結合段糾發生變形，藉此令 ^ ^彳"止使帛’然而該胃狀起子頭亦忽略其十字端部仍為驅動• M3 5 8701 V. New description: [New technical field] This creation is about a kind of screwdriver head structure that prevents rapid damage. In detail, it is about a time when the deformation can be extended during use for warning. Use the agency to ensure the safety of the job design. [Prior Art] According to Taiwan, Taiwan is a kingdom of industrial technology. From manufacturing, processing to maintenance, it is not—not advanced in technology and difficult to manufacture. Therefore, Gongxia products are well received by the world’s countries and are processed from automobile manufacturing companies. Abundant benefits, and the most commonly used equipment in the industry for many operations is the hand tool 'shaft part with high technical and dangerous environment has been replaced by machines, the basic processing and maintenance must be based on The assistance of the hand tools can be completed, so the industry players all have to develop a more flexible, more humane and cheaper structure. In the hand tools of the public hand tools, the hand tools of the starter type are the most frequently used and manufactured, especially in order to allow the user to easily replace the tools of the different head types during the operation. The relevant manufacturers have developed her (4) Hit the H _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _习 The conventional driver head is shown in the figure-picture, which includes a driving section and a Du Ren section 92, which is equivalent to the length of the coupling section 92, and the diameter of the driving section 91 is only slightly smaller than ^92' and the coupling section 92 is used in combination with a driver or a pneumatic tool, whereby it can be rotated to rotate the drive section 91 into the fixed object to be engaged, but the drive section 91 can be used with the lock piece The combination of the extinction and the end will be designed to form a shape that can be fitted with the lock, that is, as shown in the first figure, the IE movement I and 91 of the stalker show that the end portion is cut inward to form a cross state, and Screwdriver•M358701 The shape of the cup-shaped structure is the force of the shearing force of the screwdriver. “Curry coffee 1 plus ar St is the torque value multiplied by the radius of the section and then the inertia moment of the surface.” She is "ugly (10) -lnertia" and the drive section 91 is coupled with the joint section 92, so it is a type of tandem rod, and the torsion _ of the section 91 and the joint section 92, thus according to the above-mentioned torsion shear Under the stress gauge, the torque value is the same, and the smaller the radius of the section, the larger the moment of inertia is. Torsional shear stress, plus 'the shape of the side of the cross end of the broken end of the drunk path as the overall minimum, so it is also the maximum enchantment shear stress, this "the most secretive side of the fault on the side of the S" As shown in the figure of the ninth figure (in order to make it clear and easy to understand, the experimental curve diagram of the torque of the conventional screwdriver is placed in the ninth figure to facilitate comparison with the analysis of the creation, which is described in advance), the graph The vertical axis is the torsion deformation (that is, the turning shape caused by the torsion stress), and the transverse yaw is the torque value of the screwdriver head. When the torque value is raised, the screwdriver _ generates a torsional deformation, and when the torque is reached, the torque is obtained. The maximum value of elastic recovery, the so-called torsion point of the torque "yieid p〇", the trend of the curve stops at the gamma, which represents the destruction of the starter at the point of the fall, and the display is the cross end A break occurs (as shown in the second figure), and it can be seen after observing the graph. It is the damage immediately when the torque value reaches the drop point, and the torque deformation curve without buffer after the drop point (ie Plastic deformation zone after the drop point "_仙_" The plastic deformation zone is the elastic deformation zone "elastlc". The deformation of the object in the elastic deformation zone can return to the original state after the force is unloaded, and the plastic deformation zone will produce permanent deformation, even if the force is unloaded, it cannot be restored to the original state. Therefore, when the user uses the driver's head, it is easy to break the end portion, causing the end of the broken portion to be wounded, or the user may be leaning forward due to inertia; "(Subhead is second As shown in the figure, the length of the driving segment is smaller than that of the combined section 94 4 'M358701:94', so it can be regarded as two cranes of different lengths and diameters connected in series, when the head of the _ In the case of force, since the torsional force phase is inversely proportional to the polar moment of inertia, the torsion J stress U of the driving section 93 is large, so the driving section (10) will be corrected by the combined section. Deformation, thereby making ^^彳"stop 帛' However, the stomach-shaped screwdriver head also ignores that the cross end is still driven
&93中取j半讀’目而如第十—圖圖式解（為求令人明瞭易懂，該習 用起子頭之扭力實驗曲線圖係擺置於第十—圖以方便與本創作分析比較， 合先敘明），在1轉段93端部未韻之情形下，該起子输前述習知者表 <之扭力變祕伸，其曲線係較顯示^前述習峡子頭驅動段91 t所無法呈現之扭力變形，而令降伏點位置發生改變呈後移之型態，但 〃政伸了扭力變料線，在到達降舰時其十字端部仍是直接發生破 壞（如第四®賦麻）’降健魅無緩衝之扭力變職線走向，令使用 者僅是短钱受起子觀脅快速發生端部破壞，使人反财及而無法馬 上卜止作業，因此其實祕仍相料足，故有必要加以研發可於使用時延 長欠幵為間以供警不制者並確保作業安全之起子頭結構。 【新型内容】 本創作之主要目的係在於提供—種防急速損壞之起子頭結構，其可改 。”之（子頭其結構型態於使用時容易發生驅動端部急速破壞而發生危 險等缺失。 為達成别述之創作目的，本創作係包括一結合部及一作業部，其中·· 4作業部係包括一驅動端及一過渡段，該過渡段係設有一與驅動端銜 接之第—頸部、—與結合部銜接之第二頸部，以及-位於第-頸部與第二 5 M358701 ，員狀間，且直徑較第一頸部與第二頸部為小之緩衝部，該過渡段係呈由 第㈣至緩衝4直徑逐漸縮減，再由緩衝部至第二頸部直徑逐漸增加之 7内凹n m此在猶段巾形成—斷面面積較小之區域，故根據扭轉 U十算式扭轉身應力係與極慣性矩成反比，而與半徑成正比，然而 極ί貝性矩係為對半控二次乘方之面積積分，因而半徑增加會使極慣性矩有 才田大&度之增長’她之下，半徑對扭轉剪應力之貢獻較極慣性矩為小， 故在扭力值相同之情形下，半徑越小處所生之扭轉剪應力則越大，因而本 創作之U於過渡段之第_頸部與第二頸部間形成斷面面積較小之緩衝 部，因而摘較狀扭力時，緩騎辑之產生扭力Μ，而由於緩衝 部之斷面幢小，當扭力增大時，其產生之扭力變形也更為增加，故當 驅動端未破壞之情形下，緩衝部即已逐漸產生可令使用者感知之扭力變 I因此使物卩可停蝴，概鶴着蝴損歡危險狀況。 林ΓΓ作可說是—具有實雜及進步性之創作，相當值得產 業界來推廣，並公諸於社會大眾。 【實施方式】 本創作係有關於一種防急速 構，睛參閱第五圖至第七 不…'匕括—結合部1及-作業部2，其中： 该結合部1外周得呈&、喜 m係，藉此使用者可以如起 裝置與結合部1 定 于1動工具寺 μ丨I 輸2舰合部1鱗成—體，俾當 轉動時，作業部2係受帶動旋轉，因而與作業 即可被驅動獻欲結合對象_定； 、一之鎖固件 該作業部2係包括一驅動端21及一過渡段22 例所說明之驅動 6 M358701&93 takes j half-reading 'the same as the tenth-illustration solution (for the sake of clarity and easy to understand, the experimental torque diagram of the practical screwdriver head is placed in the tenth - to facilitate the creation of this Analyze and compare, in the first narrative), in the case where the end of the 1st turn 93 is not rhyme, the screwdriver is transformed into the above-mentioned conventional table <the torque is changed to the secret, and the curve is compared with the display ^the aforementioned Xixiazi head drive The torsion deformation that can not be represented by the segment 91 t, and the position of the relief point changes to a backward displacement pattern, but the government has extended the torsion variable line, and the cross end is still directly damaged when the ship is reached (eg, Four® 麻 )) 'Fatjian charm unbuffered torque to change the line, so that the user is only a short money by the start of the threat to quickly break the end of the damage, making people anti-finance and can not immediately stop the operation, so the secret It is still quite sufficient, so it is necessary to develop a screwdriver head structure that can be used to extend the deficiencies to the police and ensure the safety of the operation. [New content] The main purpose of this creation is to provide a screwdriver head structure that prevents rapid damage, which can be modified. "The structure of the sub-head is prone to the rapid destruction of the drive end and the danger of the drive end is lost. In order to achieve the purpose of creation, the creation department includes a joint part and a work part, among which 4 work The department includes a driving end and a transition section, the transition section is provided with a first neck that is engaged with the driving end, a second neck that is engaged with the joint, and - a first neck and a second 5 M358701 , between the members, and having a smaller diameter than the first neck portion and the second neck portion, the transition portion is gradually reduced from the fourth (th) to the buffer 4 diameter, and the diameter from the buffer portion to the second neck portion is gradually increased. The recessed nm of 7 is formed in the area of the U.S. section, and the area of the cross section is small. Therefore, the torsional U stress system is inversely proportional to the polar moment of inertia, and is proportional to the radius, but is extremely proportional to the radius. In order to integrate the area of the semi-control quadratic power, the increase of the radius will increase the polar moment of inertia and the growth of the degree. Under her, the contribution of the radius to the torsional shear stress is smaller than the polar moment of inertia, so the torque is In the case of the same value, the smaller the radius The torsional shear stress is larger. Therefore, the U of the present invention forms a buffer portion having a smaller cross-sectional area between the neck portion and the second neck portion of the transition section, and thus the torsion force is generated when the torque is picked up. However, since the section of the buffer portion is small, when the torque is increased, the torsional deformation is further increased. Therefore, when the driving end is not broken, the buffer portion gradually generates a torque that can be perceived by the user. Change I therefore makes the object stop, and the crane is in danger of being damaged. Lin Biao's work can be said to be a complex and progressive creation, which is worthy of promotion by the industry and publicized to the public. Embodiments of the present invention relate to an anti-rapid structure, and the eyes are referred to the fifth to seventh non-combined parts 1 and the working unit 2, wherein: the outer periphery of the joint portion 1 is & Therefore, the user can set the 1st and the lower part of the 1st movable part of the 1st movable device to the joint part 1 as the device and the joint part 1. When the rotation is performed, the working part 2 is driven to rotate, and thus the work is performed. Can be driven to combine with the object _ fixed; The 2 series includes a driving end 21 and a transition section 22. The driving method described in the example 6 M358701
端21係為十字型態之頭部，而該過渡段22係設有一與 颈部221、一與結合部丨銜接之第二頸部222， 馬區 動端21銜接之第 以及一位於第—頸部221 與第一頌部222之間，且直徑較第一頸部221與第 部223，本實施例過渡段22之型態係呈由第一頸部221至緩衝部呦直徑 逐漸縮減’再由緩衝部223至第二頸部222直徑逐漸增加之弧形内凹型離， 因此在過渡段22中形成_斷面面積較小之區域，而根據前述之扭轉煎應力 計算式，轉剪應力倾極紐矩狀比，而財徑紅比，然而極慣性 矩係為對半徑二次財之面積積分，因而伟增加會餘雛矩有相當大 -頸部222為小之緩衝 幅度之增長，相較之下，半徑對扭轉剪應力之貢獻較極慣性矩為小，故在 扭力值相同之情形下’半徑越候所生之扭轉剪應力_大，因而本創作 之型態係於過渡段22之第-頸部221與第二頸部故間形成斷面面積較小 之緩衝部223,因而本創作受到之扭力時，緩衝部M亦隨之產生扭力變形， 而由於缓衝部223之斷面面積較小’當扭力增树，其產生之扭力變形也The end portion 21 is a cross-shaped head, and the transition portion 22 is provided with a second neck portion 222 that is engaged with the neck portion 221 and the joint portion, and the first end of the horse's movable end 21 is connected to the first portion. Between the neck portion 221 and the first crotch portion 222, and having a smaller diameter than the first neck portion 221 and the second portion 223, the shape of the transition portion 22 of the present embodiment is gradually reduced from the first neck portion 221 to the buffer portion. Further, the arc portion of the buffer portion 223 to the second neck portion 222 is gradually increased in diameter, so that a region having a small cross-sectional area is formed in the transition portion 22, and the shear stress is calculated according to the aforementioned torsional frying stress calculation formula. The polar moment ratio is compared with the red ratio of the financial path, but the polar moment of inertia is the area integral of the radius of the second fiscal, so the increase in the margin will be quite large - the neck 222 is a small buffer increase. In contrast, the contribution of the radius to the torsional shear stress is smaller than the polar moment of inertia. Therefore, in the case where the torque value is the same, the torsional shear stress generated by the radius is larger, so the type of the creation is in the transition section. A buffer portion 223 having a smaller cross-sectional area is formed between the first neck portion 221 and the second neck portion 22 Therefore, when the creation is subjected to the torsion, the buffer portion M is also deformed by the torsion, and since the buffer portion 223 has a small cross-sectional area, when the torque is increased, the torsional deformation is also generated.
更為增加’故當驅動端21未破壞之情形下，緩衝部223即已逐漸產生可令 使用者感知之扭力獅，因此使用者即可停止健，以防止驅動端21發生 急速損壞之危險狀況；另外’該第二頸部222係設有—外周呈圓柱狀之辨 識部2221，該辨識部2221係具有顏色外觀，因而該辨識部2221係可用以 定義驅動端21之規格尺寸，令使用者望知即可辨識得知其為何許款式之工 具頭； 如第八圖至第十-圖所示（第八圖與第十圖為同樣本創作之扭力—扭 力變形曲線示《’而為使本創作得與習知技術清楚比較，故以第八圖與 第九圖第知技術、第十圖與第十—㈣二款習知技術上下列圖表示 7 M358701 之方式說明’合先敘明），第八圖與第十圖顯示本創作在受到扭力時，扭力 變形Μ之增加，在扭力到耕伏赠，其產生之扭力變形皆射恢復之 彈性變雜域，而當扭力超研伏點後，扭力變形即進人無法恢復之塑性 變形區域，本創作藉由過渡段22之型態，其在降仇點後之扭力變形曲線仍 逐漸延伸，即扭力值未顯著增加，但扭力變形卻持續大幅增加之塑性變形 區’在此變形延時階段，使用者即可感知過渡段22之變形並馬上停止作業 以避免危險’而不會如第九圖及第十—圖所示第_、二款f知技術在扭力 籲到達降伏點時即發生破壞之情形，故本創作過渡段22内凹型態之緩衝部挪 確實可產生在鶴端21未破猶即有相料間之扭力變觀時效果，因此 使用者會感受到本創作因扭力所生之變形及變形延時，而非習知技術之瞬 間破壞，故可確實提供警示之效果。 本創作之使用狀態如第十二圖及第十三圖所示，其中第十二圖圖式係 本創作與-氣動工具3結合，使用者持用該氣動工具3將與本創作驅動端 21鼓合之螺固件4驅動旋入欲固定對象内，當作業部2受到之扭力值上升 籲時’緩觸223亦隨之魅扭力變形，即如第十三圖所示，緩衝部挪在 超過降伏點後之變形延時階段係產生不可回復之永久變形，其變形紋路亦 顯示於過渡段22上，此時個者即可感知緩衝部挪之變形並停止作業， 以防止驅動端21突然發生崩壞之危險狀況。 由上所述者僅為用以解釋本創作之較佳實施例，並非企圖據以對本創 .作做任何形式上之限制，是以，凡有在相同之創作精神下所做有關本創作 之任何_或變更者，皆仍應包括在本創作意_護之範嗜内。 综上所述’本創作防急速損壞之起子頭結構在結構設計、使用實用性 8 M358701 是’確實是完全符合產業上發展所需，额揭露之結構創作亦 /謂未有__造，_其具有「新酿」應無 •可較之習知結構更具功效之增進，因此亦具有「進步性」，其完全符人_ •月早… 申明要件的規疋’乃依法提起專利申請，並敬請狗 局早日審查，並給予肯定。 、勺 【圖式簡單說明】 ;一、二圖係第-款習用之起子頭示意圖。 二、四騎第二款之起子頭示意圖。 紅圖係柚作防魏魏之起子職 第六圖係本創作防各、丹股外蜣不思圖。 第七权好聰解面示意圖。 第七圖係本創作防急速損壞之 第八圖係本創作防急速損壞之起子 第九圖係第-款習用之起子頭扭力扭力變形曲線示意圖。 第十圖係本創作防急速損壞 2變形曲線示意圖。 第十一圖係第二款習用之起子頭扭力二^力―扭力變形曲線示意圖。 【主要元件符號二Γ她之起子頭使_及變形示意圖。 苐一款習用之起子頭： 91驅動段92結合段 弟一款習用之起子頭： 93驅動段 94結合段 本創作： ^結合部2作業部21 22過渡段221 頸部22 ^ 223緩衝部2221辨識部 4螺固件 乳動工具 9Further increase, so when the drive end 21 is not broken, the buffer portion 223 has gradually produced a torque lion that can be perceived by the user, so that the user can stop the health to prevent the dangerous situation of the drive end 21 from being rapidly damaged. Further, the second neck portion 222 is provided with an identification portion 2221 having a cylindrical outer circumference, and the identification portion 2221 has a color appearance, so that the identification portion 2221 can be used to define the size of the driving end 21, so that the user Looking at the tool head to identify the type of the model; as shown in the eighth to tenth-pictures (the eighth and tenth drawings are the same torque of the creation - the torsion deformation curve shows "' This creation is clearly compared with the prior art, so the following diagrams of the 8th and 9th diagrams of the prior art, the tenth and the tenth (four) of the prior art show the way of the description of the 7 M358701 ), the eighth and tenth figures show that when the creation is subjected to torsion, the torsion deformation increases, and in the torque to the ploughing, the resulting torsional deformation is the elastic variable domain of the recovery, and when the torque is super-revolution After the point, the torque deformation is progressing The plastic deformation zone that cannot be recovered, the creation of the transition section 22, the torsion deformation curve after the hatred point is still extended, that is, the torque value does not increase significantly, but the torsional deformation continues to increase the plastic deformation zone 'In this deformation delay phase, the user can perceive the deformation of the transition section 22 and immediately stop the operation to avoid danger', but not as shown in the ninth and tenth-figure diagrams. When the arrival point is reached, the damage occurs. Therefore, the concave portion of the concave portion of the creation transition section 22 can be produced when the crane end 21 is not broken, that is, the effect of the torque between the materials is changed, so the user will It is felt that the deformation and deformation delay caused by the torque of the creation is not the instantaneous destruction of the prior art, so the warning effect can be surely provided. The use state of the creation is as shown in the twelfth and thirteenth drawings, wherein the twelfth figure is the combination of the creation and the pneumatic tool 3, and the user holds the pneumatic tool 3 with the creation drive end 21 The screwing screw 4 is driven into the object to be fixed, and when the torque value of the working portion 2 is increased, the slow touch 223 is also deformed by the charm torque, that is, as shown in the thirteenth figure, the buffer portion is moved over. The deformation delay phase after the relief point produces a non-recoverable permanent deformation, and the deformation texture is also displayed on the transition section 22, at which time one can sense the deformation of the buffer portion and stop the operation to prevent the drive end 21 from suddenly collapsing. Bad danger situation. The above description is only for explaining the preferred embodiment of the present creation, and is not intended to impose any form of restriction on the creation of the creation, that is, the creation of the creation in the same creative spirit. Any _ or changer should still be included in this creative meaning. In summary, the design of the scratch-proof head structure of this creation is in the structural design and practical use. 8 M358701 is 'completely in line with the needs of the development of the industry. The structure of the disclosure is also __made, _ It has the "new brewing" should be no. It can be more effective than the conventional structure. Therefore, it is also "progressive". It is completely viable. _ • Months early... The stipulation of the requirements is a patent application in accordance with the law. And please the dog bureau to review it early and give it affirmation. Spoon [Simple description of the diagram]; The first and second diagrams are the schematic diagrams of the first chapter. Second, the fourth rider of the second section of the screwdriver. The red figure is made of pomelo for the prevention of Wei Weizhi. The sixth picture is the creation of this novel, and the Dan shares are not considered. The seventh right is good to solve the schematic diagram. The seventh picture is the creation of the anti-rapid damage of the creation. The eighth picture is the starter of the creation of the anti-rapid damage. The ninth picture is the schematic diagram of the torque curve of the torque head of the screwdriver. The tenth figure is a schematic diagram of the deformation curve of this creation against rapid damage. The eleventh figure is a schematic diagram of the second conventionally used torque head two-force-torque deformation curve. [The main component symbol is the 起 and the deformation diagram of her screwdriver.苐 A conventional screwdriver head: 91 drive segment 92 combined with a younger brother of a conventional screwdriver: 93 drive segment 94 combined with the segment of the creation: ^ joint 2 working part 21 22 transition section 221 neck 22 ^ 223 buffer 2221 Identification part 4 screw firmware tool 9